////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2018-2021 The Octave Project Developers
//
// See the file COPYRIGHT.md in the top-level directory of this
// distribution or <https://octave.org/copyright/>.
//
// This file is part of Octave.
//
// Octave is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Octave is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Octave; see the file COPYING.  If not, see
// <https://www.gnu.org/licenses/>.
//
////////////////////////////////////////////////////////////////////////

#if defined (HAVE_CONFIG_H)
#  include "config.h"
#endif

#include <sstream>
#include <string>

#include "f77-fcn.h"
#include "lo-sysinfo.h"
#include "oct-shlib.h"

// Hack to stringize macro results.
#define xSTRINGIZE(x) #x
#define STRINGIZE(x) xSTRINGIZE(x)

namespace octave
{
  namespace sys
  {
    std::string blas_version (void)
    {
      dynamic_library dyn_libs ("");

      if (! dyn_libs)
        return "unknown BLAS";

      std::string retval;

      // Check for functions that are specific to certain BLAS implementations.

      // FlexiBLAS
      typedef void (*flexi_f_type) (int *, int *, int *);
      flexi_f_type flexi_f_ptr = reinterpret_cast<flexi_f_type>
                                 (dyn_libs.search ("flexiblas_get_version"));

      if (flexi_f_ptr)
        {
          int v_major = 0;
          int v_minor = 0;
          int v_patch = 0;
          flexi_f_ptr (&v_major, &v_minor, &v_patch);

          std::ostringstream s;
          s << "FlexiBLAS Version "
            << v_major << "." << v_minor << "." << v_patch;

          retval = s.str ();
        }

      // OpenBLAS
      typedef char * (*open_fcn_type) (void);
      open_fcn_type open_f_ptr = reinterpret_cast<open_fcn_type>
                                 (dyn_libs.search ("openblas_get_config"));

      if (open_f_ptr)
        {
          if (! retval.empty ())
            retval += "\n";

          retval += "OpenBLAS (config: " + std::string (open_f_ptr ()) + ")";
        }

      // OpenBLAS with minimal extension functions included in the library
      else if (dyn_libs.search ("openblas_get_num_threads"))
        {
          if (! retval.empty ())
            retval += "\n";

          retval += "OpenBLAS (config: unknown)";
        }

      // GotoBLAS(2)
      if (dyn_libs.search ("gotoblas_profile_init"))
        {
          if (! retval.empty ())
            retval += "\n";

          retval += "GotoBLAS(2)";
        }

      // ATLAS
      // FIXME: If we are really interested, we could use a pipe to
      // redirect the output of "ATL_buildinfo".
      if (dyn_libs.search ("ATL_buildinfo"))
        {
          if (! retval.empty ())
            retval += "\n";

          retval += "ATLAS";
        }

      // ACML
      typedef void (*acml_f_type) (int *, int *, int *);
      acml_f_type acml_f_ptr = reinterpret_cast<acml_f_type>
                               (dyn_libs.search ("acmlversion"));

      if (acml_f_ptr)
        {
          int v_major = 0;
          int v_minor = 0;
          int v_patch = 0;
          acml_f_ptr (&v_major, &v_minor, &v_patch);

          std::ostringstream s;
          s << "ACML BLAS Version "
            << v_major << "." << v_minor << "." << v_patch;

          if (! retval.empty ())
            retval += "\n";

          retval += s.str ();
        }

      // Intel MKL
      typedef void (*mkl_f_type) (char *, int);
      mkl_f_type mkl_f_ptr = reinterpret_cast<mkl_f_type>
                             (dyn_libs.search ("mkl_get_version_string"));

      if (mkl_f_ptr)
        {
          char buf[198];
          int len = 198;
          mkl_f_ptr (buf, len);

          if (! retval.empty ())
            retval += "\n";

          retval += std::string (buf);
        }

      // Otherwise
      if (retval.empty ())
        retval = "unknown or reference BLAS";

      return retval;
    }

    std::string lapack_version (void)
    {
      std::string retval = "unknown LAPACK";

      dynamic_library dyn_libs ("");

      if (! dyn_libs)
        return retval;

      // query LAPACK version
      typedef F77_RET_T
        (*ilaver_fcn_type) (const F77_INT&, const F77_INT&, const F77_INT&);
      ilaver_fcn_type f_ptr = reinterpret_cast<ilaver_fcn_type>
        (dyn_libs.search (STRINGIZE (F77_FUNC (ilaver, ILAVER))));

      if (f_ptr)
        {
          int v_major = 0;
          int v_minor = 0;
          int v_patch = 0;
          f_ptr (v_major, v_minor, v_patch);

          std::ostringstream s;
          s << "Linear Algebra PACKage Version "
            << v_major << "." << v_minor << "." << v_patch;

          retval = s.str ();
        }

      return retval;
    }
  }
}